2024RNAAS...8..155M

The weak line of Hg II located at 5677.10 Å is used to measure the mercury abundance in two HgMn stars, HD 143807 (ι CrB) and HD 16727 (11 Per). This line is detected at 3σ above the noise in the adjacent continuum in HD 143807 but not detected in HD 16727. The synthesis of this line, using the current atomic parameters available in NIST, confirms the large overabundance of mercury in HD 143807, about +4.60 dex, in very good agreement with the excess derived in earlier studies from the 3983.93 Å line. At the overabundance expected for HD 16727 (3.90 dex), the line is predicted to contribute a 1% absorption feature which is not seen in the observed spectrum.